1. Field of the Invention
The present invention relates to a cut sheet feeder for a word processor, an electrophotographic copier, a printer, a facsimile machine or another image forming apparatus.
2. Description of Related Art
For example, the assignee's Japanese Patent Application Laid-Open No. 7-304527 discloses a conventional printer, which includes an operation panel formed in a front portion of the top of its housing. A sheet cassette is positioned in the rear of the panel, and held removably in an backwardly inclined position by the housing. A cut sheet of paper can be fed from the cassette toward a print unit (image forming unit), which is supported in the housing.
The sheet cassette includes a support plate, which is urged upward. The cassette also includes a bottom support in the form of a bank. The front or lower ends of the sheets stacked on the support plate are stopped by the bottom support. Semi-cylindrical pickup rollers are supported downstream from the bottom support, and can be turned intermittently. A holder is urged toward and radially of the rollers, and includes a separation pad, which has a high friction factor, for contact with the cylindrical surfaces of the rollers. The front ends of the sheets on the support plate can be separated one by one, and the sheets can then be fed one after one toward the print unit.
However, if thick post cards, envelopes or other relatively rigid sheets are stacked in the cassette, their front ends may be stopped by the rear end face of the holder, and may not transfer or move smoothly onto the upper surface of the holder. Consequently, the sheets may not be fed smoothly by the turning of the pickup rollers.